Particulates can be present in fluid flows such as the flows in a liquid chromatography system. The particulates may exist in the solvents used for the mobile phase or may be generated within the system by surfaces that move against each other. For example, internal pump components and solvent selector components can generate particulates during operation. Conventional chromatography systems sometimes utilize sintered metal filters, polymer filters and glass filters to remove particulates from the fluid stream. For example, such filters may be used to purify one or more solvents used for a mobile phase by removing particulates at the source of the solvent. These filters can also be used at the inlet or outlet of wash solvent pumps and other system pumps, and may be used to filter a sample for injection into the mobile phase. In addition, these filters are commonly provided at the inlet and outlet of a chromatographic column to retain sorbent particles inside the column while also removing particulates that may be present in the flow to the column.
Conventional filters such as polymer filters, sintered metal filters and glass filters can significantly react with the solvents used by the chromatography system. In addition, such filters may react with a chromatographic sample. These interactions can reduce the sensitivity or otherwise degrade the chromatographic separation data for the liquid chromatography system. For example, metal and glass filters can go into solution with certain solvents and potentially precipitate downstream in the fluid path. Dissolved metal and glass compounds can combine with sample compounds, resulting in changes to the physical properties of the sample compounds. These changes can alter the separation of the compounds and adversely affect the ability to detect and quantify the compounds. For mass spectrometry analysis, the mass of compounds may be changed through interactions with the filter material, leading to degradation of the mass spectrometry without the knowledge of the user. Other types of filters, such as plastic filters and the additives used in plastic filters, can solubilize into certain mobile phases and create compounds that interfere with or otherwise complicate the identification and quantitation of the analyte compounds.